added xdata decoding for KNMI Tachometer

Author: cixio

js/xdata.js

@@ -592,6 +592,37 @@ function parseSKYDEW(xdata) {
     return _output
 }
 
+function parseKnmiTachometer(xdata) {
+	// KNMI Tachometer for Vaisala OIF411
+	//
+	// Sample data:      80022B5A1EE4001384A407F8   (length = 24 characters)
+
+	// Run some checks over the input
+	if(xdata.length != 24){
+		// Invalid dataset
+		return {};
+	}
+
+	if(xdata.substr(0,2) !== '80'){
+		// Not a KNMI Tachometer (shouldn't get here)
+		return {};
+	}
+
+	var _output = {};
+
+	// uptime (in seconds) of the arduino tachometer board
+	_output['tacho_uptime'] = (parseInt(xdata.substr(4,8),16) * 8 / 1000000).toFixed();
+	
+	// time the Vaisala OIF411 motor needs to make 400 rounds
+	_delta = parseInt(xdata.substr(12,8),16) * 8 / 1000000;
+	_output['tacho_delta'] = _delta.toFixed(3); 
+	
+	// calculated rounds per second
+	_output['tacho_rps'] = (400 / _delta).toFixed(3);
+	
+	return _output
+}
+
 function parseXDATA(data, pressure, temperature){
     // Accept an XDATA string, or multiple XDATA entries, delimited by '#'
     // Attempt to parse each one, and return an object
@@ -683,8 +714,9 @@ function parseXDATA(data, pressure, temperature){
             // POPS
             if (!_instruments.includes("POPS")) _instruments.push('POPS');
         } else if (_instrument === '80'){
-            // Unknown!
-            //console.log("Saw unknown XDATA instrument 0x80.")
+			// KNMI Tachometer
+            _xdata_temp = parseKnmiTachometer(_current_xdata);
+			_output = Object.assign(_output,_xdata_temp);
         }else {
             // Unknown!